Simplify the following expression: $k = \dfrac{6z}{6x - 2} - \dfrac{2x}{6x - 2}$ You can assume $x,y,z \neq 0$.
Solution: Since the expressions have the same denominator we simply combine the numerators: $k = \dfrac{6z - (2x)}{6x - 2}$ $k = \dfrac{6z - 2x}{6x - 2}$ The numerator and denominator have a common factor of $2$, so we can simplify $k = \dfrac{3z - x}{3x - 1}$